Gluster file sys is already in the kernel, because its some NFS extension. Unfortunately in the debian Pakage, you downloaded, only the server part is implemented. Thats principially enough, cause your NAS is a server (or better is supposed to act as that).

As I remember there´s another way to use the nas as client - try wget (its already in there) and use the local IP if used in LAN.

Greetz.
Snoopy

Ps. If you would like to add fuse to kernel anyway you´ll need to compile a new version of the kernel (with fuse activated). Seems to me a little complicated - but depends on your experiences. If you would try to do so, post that! And we could try that - but its on your own risk

This means you have to take the sources from MRT and compile it. But as I know they are not up to date.
The debian Wiki article has been written by kleiner_muc.
I tried to contact him but he has not been here at the forum for quite a long time.